How to regulate a pump for garden pond?


I just built up a garden pond with a pump to filter the water and let it run over a small water fall.
The problem is, that I want to regulate the pump as the water flow is too high.
So I don’t only want to switch it on and off but I want to control the water quantity.
The pump has a brushless DC motor and the manufacturer sells a dimmer plug to control the pump.

This dimmer plug is not smart and has no memory function. So after switching off the pump the pump starts again with 100%.

My Idea was to control this pump with esp and a PWM.
Has anybody an idea how to realize this idea?

think we need a bit more info some pic make model what the voltage 240v 120v

what the Dimmer is just a light switch one there you could relace with a smart light dimmer as long as the amp are less the light switch

220/240 V, 50/60 Hz, 35 W



Get an oscilloscope and CAREFULLY measure/observe what the dimmer does when it changes settings.

It is probably a 240v PWM light dimmer, but no guarantees.

Hmmmm it may be more complicated

It seems there is some conflicting info here…

… but that is certainly a mains outlet so the motor description is probably wrong…

You can use a lot of Z-Wave dimmers (and likely ZigBee too) for speed control of fans and this pump being only 35W is only around half that of most fans. Might be the easiest solution.

is it really no problem to control a synchronous pump with a simple dimmer?
I will try but I don’t want to destroy the pump and loose the guarantee.

It should be ok. The dimmer is simply chopping the waveform to reduce the RMS voltage.

If it dies, don’t tell them you used a dimmer :wink:

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It would be simpler to buy a throttle valve than try to control the pump.

maybe you are right… it was just my idea, but it seems not that easy

but… coming back to the dimmer solution. A sonoff dimmer switch should also work, if the dimmer is fine in general?
The electronical function should be the same only the communication with ha is different. Right?

Correct. As long as the rating is adequate too.